An Outbreak of Fungal Endophthalmitis After Cataract Surgery in South Korea

Abstract

Importance: Fungal endophthalmitis caused by contaminated medical products is extremely rare; it follows an intractable clinical course with a poor visual prognosis.

Objective: To report the epidemiologic and clinical features and treatment outcomes of a nationwide fungal endophthalmitis outbreak after cataract surgery as a result of contaminated viscoelastic agents in South Korea.

Design, setting, and participants: This was a retrospective case series analysis of clinical data from multiple institutions in South Korea conducted from September 1, 2020, to October 31, 2021. Data were collected through nationwide surveys in May and October 2021 from the 100 members of the Korean Retinal Society. Patients were diagnosed with fungal endophthalmitis resulting from the use of the viscoelastic material sodium hyaluronate (Unial [Unimed Pharmaceutical Inc]). Data were analyzed from November 1, 2021, to May 30, 2022.

Main outcomes and measures: The clinical features and causative species were identified, and treatment outcomes were analyzed for patients who underwent 6 months of follow-up.

Results: The fungal endophthalmitis outbreak developed between September 1, 2020, and June 30, 2021, and peaked in November 2020. An official investigation by the Korea Disease Control and Prevention Agency confirmed contamination of viscoelastic material. All 281 eyes of 265 patients (mean [SD] age, 65.4 [10.8] years; 153 female individuals [57.7%]) were diagnosed with fungal endophthalmitis, based on clinical examinations and supportive culture results. The mean (SD) time period between cataract surgery and diagnosis was 24.7 (17.3) days. Patients exhibited characteristic clinical features of fungal endophthalmitis, including vitreous opacity (212 of 281 [75.4%]), infiltration into the intraocular lens (143 of 281 [50.9%]), and ciliary infiltration (55 of 281 [19.6%]). Cultures were performed in 260 eyes, and fungal presence was confirmed in 103 eyes (39.6%). Among them, Fusarium species were identified in 89 eyes (86.4%). Among the 228 eyes included in the treatment outcome analysis, the mean (SD) best-corrected visual acuity improved from 0.78 (0.74) logMAR (Snellen equivalent, 20/120 [7.3 lines]) to 0.36 (0.49) logMAR (Snellen equivalent, 20/45 [4.9 lines]) at 6 months. Furthermore, disease remission with no signs of fungal endophthalmitis (or cells in the anterior chamber milder than grade 1) was noted in 214 eyes (93.9%).

Conclusions and relevance: This was a retrospectively reviewed case series of a fungal endophthalmitis outbreak resulting from contaminated viscoelastic material. Findings of this case series study support the potential benefit of prompt, aggressive surgical intervention that may reduce treatment burden and improve prognosis of fungal endophthalmitis caused by contaminated medical products.

Figure 1.. Flowchart Describing Case Inclusion and Exclusion Criteria

Figure 2.. Clinical Manifestation and Treatment Course of a Female Patient Aged 56 Years With Fungal Endophthalmitis

A, An anterior segment photograph taken 16 days after phacoemulsification showing fibrin formation around the intraocular lens (IOL). B, Nineteen days after vitrectomy, severe anterior chamber fibrin formation was observed even after 7 intravitreal voriconazole injections. C, Intraoperatively, filament formation at the vitreous base was observed during the second vitrectomy with IOL removal. D, One month after secondary IOL scleral fixation, an anterior segment photograph showed a clear anterior chamber.

Figure 3.. Morphological Examination and Identification of Fusarium oxysporum

A and B, After 3 days at 30 °C, colonies on potato dextrose agar show white cottony growth and pigmentation on the bottom of plate, compatible with gross features of Fusarium species. C, Monophialides (black arrowheads) and oval to ellipsoid microconidia (yellow arrowheads) are observed on lactophenol cotton blue stain (original magnification ×1000), strongly suggesting Fusarium species. D, Mass spectrometry generated by matrix-assisted laser desorption ionization time of flight mass spectrometry (ASTA MicroIDSys [ASTA Inc]) enabled the exact identification of the species as Fusarium oxysporum. Relative intensity indicates the ratio of a certain intensity to the largest intensity peak within the acquired spectrum. m/z indicates mass to charge ratio; r, resolution; s, signal to noise ratio.

Figure 4.. Best-Corrected Visual Acuity (BCVA) Outcomes 6 Months After Treatment

IVI indicates intravitreal antifungal injection; PPV, pars plana vitrectomy.